/*
 * WPA Supplicant / PC/SC smartcard interface for USIM, GSM SIM
 * Copyright (c) 2004-2007, Jouni Malinen <j@w1.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 *
 * This file implements wrapper functions for accessing GSM SIM and 3GPP USIM
 * cards through PC/SC smartcard library. These functions are used to implement
 * authentication routines for EAP-SIM and EAP-AKA.
 */

#include "includes.h"
#include <winscard.h>

#include "common.h"
#include "pcsc_funcs.h"


/* See ETSI GSM 11.11 and ETSI TS 102 221 for details.
 * SIM commands:
 * Command APDU: CLA INS P1 P2 P3 Data
 *   CLA (class of instruction): A0 for GSM, 00 for USIM
 *   INS (instruction)
 *   P1 P2 P3 (parameters, P3 = length of Data)
 * Response APDU: Data SW1 SW2
 *   SW1 SW2 (Status words)
 * Commands (INS P1 P2 P3):
 *   SELECT: A4 00 00 02 <file_id, 2 bytes>
 *   GET RESPONSE: C0 00 00 <len>
 *   RUN GSM ALG: 88 00 00 00 <RAND len = 10>
 *   RUN UMTS ALG: 88 00 81 <len=0x22> data: 0x10 | RAND | 0x10 | AUTN
 *	P1 = ID of alg in card
 *	P2 = ID of secret key
 *   READ BINARY: B0 <offset high> <offset low> <len>
 *   READ RECORD: B2 <record number> <mode> <len>
 *	P2 (mode) = '02' (next record), '03' (previous record),
 *		    '04' (absolute mode)
 *   VERIFY CHV: 20 00 <CHV number> 08
 *   CHANGE CHV: 24 00 <CHV number> 10
 *   DISABLE CHV: 26 00 01 08
 *   ENABLE CHV: 28 00 01 08
 *   UNBLOCK CHV: 2C 00 <00=CHV1, 02=CHV2> 10
 *   SLEEP: FA 00 00 00
 */

/* GSM SIM commands */
#define SIM_CMD_SELECT			0xa0, 0xa4, 0x00, 0x00, 0x02
#define SIM_CMD_RUN_GSM_ALG		0xa0, 0x88, 0x00, 0x00, 0x10
#define SIM_CMD_GET_RESPONSE		0xa0, 0xc0, 0x00, 0x00
#define SIM_CMD_READ_BIN		0xa0, 0xb0, 0x00, 0x00
#define SIM_CMD_READ_RECORD		0xa0, 0xb2, 0x00, 0x00
#define SIM_CMD_VERIFY_CHV1		0xa0, 0x20, 0x00, 0x01, 0x08

/* USIM commands */
#define USIM_CLA			0x00
#define USIM_CMD_RUN_UMTS_ALG		0x00, 0x88, 0x00, 0x81, 0x22
#define USIM_CMD_GET_RESPONSE		0x00, 0xc0, 0x00, 0x00

#define SIM_RECORD_MODE_ABSOLUTE 0x04

#define USIM_FSP_TEMPL_TAG		0x62

#define USIM_TLV_FILE_DESC		0x82
#define USIM_TLV_FILE_ID		0x83
#define USIM_TLV_DF_NAME		0x84
#define USIM_TLV_PROPR_INFO		0xA5
#define USIM_TLV_LIFE_CYCLE_STATUS	0x8A
#define USIM_TLV_FILE_SIZE		0x80
#define USIM_TLV_TOTAL_FILE_SIZE	0x81
#define USIM_TLV_PIN_STATUS_TEMPLATE	0xC6
#define USIM_TLV_SHORT_FILE_ID		0x88

#define USIM_PS_DO_TAG			0x90

#define AKA_RAND_LEN 16
#define AKA_AUTN_LEN 16
#define AKA_AUTS_LEN 14
#define RES_MAX_LEN 16
#define IK_LEN 16
#define CK_LEN 16


typedef enum { SCARD_GSM_SIM, SCARD_USIM } sim_types;

struct scard_data {
    SCARDCONTEXT ctx;
    SCARDHANDLE card;
    DWORD protocol;
    sim_types sim_type;
    int pin1_required;
};

#ifdef __MINGW32_VERSION
/* MinGW does not yet support WinScard, so load the needed functions
 * dynamically from winscard.dll for now. */

static HINSTANCE dll = NULL; /* winscard.dll */

static const SCARD_IO_REQUEST *dll_g_rgSCardT0Pci, *dll_g_rgSCardT1Pci;
#undef SCARD_PCI_T0
#define SCARD_PCI_T0 (dll_g_rgSCardT0Pci)
#undef SCARD_PCI_T1
#define SCARD_PCI_T1 (dll_g_rgSCardT1Pci)


static WINSCARDAPI LONG WINAPI
(*dll_SCardEstablishContext)(IN DWORD dwScope,
        IN LPCVOID pvReserved1,
        IN LPCVOID pvReserved2,
        OUT LPSCARDCONTEXT phContext);
#define SCardEstablishContext dll_SCardEstablishContext

static long (*dll_SCardReleaseContext)(long hContext);
#define SCardReleaseContext dll_SCardReleaseContext

static WINSCARDAPI LONG WINAPI
(*dll_SCardListReadersA)(IN SCARDCONTEXT hContext,
        IN LPCSTR mszGroups,
        OUT LPSTR mszReaders,
        IN OUT LPDWORD pcchReaders);
#undef SCardListReaders
#define SCardListReaders dll_SCardListReadersA

static WINSCARDAPI LONG WINAPI
(*dll_SCardConnectA)(IN SCARDCONTEXT hContext,
        IN LPCSTR szReader,
        IN DWORD dwShareMode,
        IN DWORD dwPreferredProtocols,
        OUT LPSCARDHANDLE phCard,
        OUT LPDWORD pdwActiveProtocol);
#undef SCardConnect
#define SCardConnect dll_SCardConnectA

static WINSCARDAPI LONG WINAPI
(*dll_SCardDisconnect)(IN SCARDHANDLE hCard,
        IN DWORD dwDisposition);
#define SCardDisconnect dll_SCardDisconnect

static WINSCARDAPI LONG WINAPI
(*dll_SCardTransmit)(IN SCARDHANDLE hCard,
        IN LPCSCARD_IO_REQUEST pioSendPci,
        IN LPCBYTE pbSendBuffer,
        IN DWORD cbSendLength,
        IN OUT LPSCARD_IO_REQUEST pioRecvPci,
        OUT LPBYTE pbRecvBuffer,
        IN OUT LPDWORD pcbRecvLength);
#define SCardTransmit dll_SCardTransmit

static WINSCARDAPI LONG WINAPI
(*dll_SCardBeginTransaction)(IN SCARDHANDLE hCard);
#define SCardBeginTransaction dll_SCardBeginTransaction

static WINSCARDAPI LONG WINAPI
(*dll_SCardEndTransaction)(IN SCARDHANDLE hCard, IN DWORD dwDisposition);
#define SCardEndTransaction dll_SCardEndTransaction


static int mingw_load_symbols(void)
{
    char *sym;

    if (dll)
        return 0;

    dll = LoadLibrary("winscard");
    if (dll == NULL) {
        wpa_printf(MSG_DEBUG, "WinSCard: Could not load winscard.dll "
                "library");
        return -1;
    }

#define LOADSYM(s) \
    sym = #s; \
    dll_ ## s = (void *) GetProcAddress(dll, sym); \
    if (dll_ ## s == NULL) \
    goto fail;

    LOADSYM(SCardEstablishContext);
    LOADSYM(SCardReleaseContext);
    LOADSYM(SCardListReadersA);
    LOADSYM(SCardConnectA);
    LOADSYM(SCardDisconnect);
    LOADSYM(SCardTransmit);
    LOADSYM(SCardBeginTransaction);
    LOADSYM(SCardEndTransaction);
    LOADSYM(g_rgSCardT0Pci);
    LOADSYM(g_rgSCardT1Pci);

#undef LOADSYM

    return 0;

fail:
    wpa_printf(MSG_DEBUG, "WinSCard: Could not get address for %s from "
            "winscard.dll", sym);
    FreeLibrary(dll);
    dll = NULL;
    return -1;
}


static void mingw_unload_symbols(void)
{
    if (dll == NULL)
        return;

    FreeLibrary(dll);
    dll = NULL;
}

#else /* __MINGW32_VERSION */

#define mingw_load_symbols() 0
#define mingw_unload_symbols() do { } while (0)

#endif /* __MINGW32_VERSION */


static int _scard_select_file(struct scard_data *scard, unsigned short file_id,
        unsigned char *buf, size_t *buf_len,
        sim_types sim_type, unsigned char *aid,
        size_t aidlen);
static int scard_select_file(struct scard_data *scard, unsigned short file_id,
        unsigned char *buf, size_t *buf_len);
static int scard_verify_pin(struct scard_data *scard, const char *pin);
static int scard_get_record_len(struct scard_data *scard,
        unsigned char recnum, unsigned char mode);
static int scard_read_record(struct scard_data *scard,
        unsigned char *data, size_t len,
        unsigned char recnum, unsigned char mode);


static int scard_parse_fsp_templ(unsigned char *buf, size_t buf_len,
        int *ps_do, int *file_len)
{
    unsigned char *pos, *end;

    if (ps_do)
        *ps_do = -1;
    if (file_len)
        *file_len = -1;

    pos = buf;
    end = pos + buf_len;
    if (*pos != USIM_FSP_TEMPL_TAG) {
        wpa_printf(MSG_DEBUG, "SCARD: file header did not "
                "start with FSP template tag");
        return -1;
    }
    pos++;
    if (pos >= end)
        return -1;
    if ((pos + pos[0]) < end)
        end = pos + 1 + pos[0];
    pos++;
    wpa_hexdump(MSG_DEBUG, "SCARD: file header FSP template",
            pos, end - pos);

    while (pos + 1 < end) {
        wpa_printf(MSG_MSGDUMP, "SCARD: file header TLV "
                "0x%02x len=%d", pos[0], pos[1]);
        if (pos + 2 + pos[1] > end)
            break;

        if (pos[0] == USIM_TLV_FILE_SIZE &&
                (pos[1] == 1 || pos[1] == 2) && file_len) {
            if (pos[1] == 1)
                *file_len = (int) pos[2];
            else
                *file_len = ((int) pos[2] << 8) |
                    (int) pos[3];
            wpa_printf(MSG_DEBUG, "SCARD: file_size=%d",
                    *file_len);
        }

        if (pos[0] == USIM_TLV_PIN_STATUS_TEMPLATE &&
                pos[1] >= 2 && pos[2] == USIM_PS_DO_TAG &&
                pos[3] >= 1 && ps_do) {
            wpa_printf(MSG_DEBUG, "SCARD: PS_DO=0x%02x",
                    pos[4]);
            *ps_do = (int) pos[4];
        }

        pos += 2 + pos[1];

        if (pos == end)
            return 0;
    }
    return -1;
}


static int scard_pin_needed(struct scard_data *scard,
        unsigned char *hdr, size_t hlen)
{
    if (scard->sim_type == SCARD_GSM_SIM) {
        if (hlen > SCARD_CHV1_OFFSET &&
                !(hdr[SCARD_CHV1_OFFSET] & SCARD_CHV1_FLAG))
            return 1;
        return 0;
    }

    if (scard->sim_type == SCARD_USIM) {
        int ps_do;
        if (scard_parse_fsp_templ(hdr, hlen, &ps_do, NULL))
            return -1;
        /* TODO: there could be more than one PS_DO entry because of
         * multiple PINs in key reference.. */
        if (ps_do > 0 && (ps_do & 0x80))
            return 1;
        return 0;
    }

    return -1;
}


static int scard_get_aid(struct scard_data *scard, unsigned char *aid,
        size_t maxlen)
{
    int rlen, rec;
    struct efdir {
        unsigned char appl_template_tag; /* 0x61 */
        unsigned char appl_template_len;
        unsigned char appl_id_tag; /* 0x4f */
        unsigned char aid_len;
        unsigned char rid[5];
        unsigned char appl_code[2]; /* 0x1002 for 3G USIM */
    } *efdir;
    unsigned char buf[100];
    size_t blen;

    efdir = (struct efdir *) buf;
    blen = sizeof(buf);
    if (scard_select_file(scard, SCARD_FILE_EF_DIR, buf, &blen)) {
        wpa_printf(MSG_DEBUG, "SCARD: Failed to read EF_DIR");
        return -1;
    }
    wpa_hexdump(MSG_DEBUG, "SCARD: EF_DIR select", buf, blen);

    for (rec = 1; rec < 10; rec++) {
        rlen = scard_get_record_len(scard, rec,
                SIM_RECORD_MODE_ABSOLUTE);
        if (rlen < 0) {
            wpa_printf(MSG_DEBUG, "SCARD: Failed to get EF_DIR "
                    "record length");
            return -1;
        }
        blen = sizeof(buf);
        if (rlen > (int) blen) {
            wpa_printf(MSG_DEBUG, "SCARD: Too long EF_DIR record");
            return -1;
        }
        if (scard_read_record(scard, buf, rlen, rec,
                    SIM_RECORD_MODE_ABSOLUTE) < 0) {
            wpa_printf(MSG_DEBUG, "SCARD: Failed to read "
                    "EF_DIR record %d", rec);
            return -1;
        }
        wpa_hexdump(MSG_DEBUG, "SCARD: EF_DIR record", buf, rlen);

        if (efdir->appl_template_tag != 0x61) {
            wpa_printf(MSG_DEBUG, "SCARD: Unexpected application "
                    "template tag 0x%x",
                    efdir->appl_template_tag);
            continue;
        }

        if (efdir->appl_template_len > rlen - 2) {
            wpa_printf(MSG_DEBUG, "SCARD: Too long application "
                    "template (len=%d rlen=%d)",
                    efdir->appl_template_len, rlen);
            continue;
        }

        if (efdir->appl_id_tag != 0x4f) {
            wpa_printf(MSG_DEBUG, "SCARD: Unexpected application "
                    "identifier tag 0x%x", efdir->appl_id_tag);
            continue;
        }

        if (efdir->aid_len < 1 || efdir->aid_len > 16) {
            wpa_printf(MSG_DEBUG, "SCARD: Invalid AID length %d",
                    efdir->aid_len);
            continue;
        }

        wpa_hexdump(MSG_DEBUG, "SCARD: AID from EF_DIR record",
                efdir->rid, efdir->aid_len);

        if (efdir->appl_code[0] == 0x10 &&
                efdir->appl_code[1] == 0x02) {
            wpa_printf(MSG_DEBUG, "SCARD: 3G USIM app found from "
                    "EF_DIR record %d", rec);
            break;
        }
    }

    if (rec >= 10) {
        wpa_printf(MSG_DEBUG, "SCARD: 3G USIM app not found "
                "from EF_DIR records");
        return -1;
    }

    if (efdir->aid_len > maxlen) {
        wpa_printf(MSG_DEBUG, "SCARD: Too long AID");
        return -1;
    }

    os_memcpy(aid, efdir->rid, efdir->aid_len);

    return efdir->aid_len;
}


/**
 * scard_init - Initialize SIM/USIM connection using PC/SC
 * @sim_type: Allowed SIM types (SIM, USIM, or both)
 * Returns: Pointer to private data structure, or %NULL on failure
 *
 * This function is used to initialize SIM/USIM connection. PC/SC is used to
 * open connection to the SIM/USIM card and the card is verified to support the
 * selected sim_type. In addition, local flag is set if a PIN is needed to
 * access some of the card functions. Once the connection is not needed
 * anymore, scard_deinit() can be used to close it.
 */
struct scard_data * scard_init(scard_sim_type sim_type)
{
    long ret;
    unsigned long len;
    struct scard_data *scard;
#ifdef CONFIG_NATIVE_WINDOWS
    TCHAR *readers = NULL;
#else /* CONFIG_NATIVE_WINDOWS */
    char *readers = NULL;
#endif /* CONFIG_NATIVE_WINDOWS */
    unsigned char buf[100];
    size_t blen;
    int transaction = 0;
    int pin_needed;

    wpa_printf(MSG_DEBUG, "SCARD: initializing smart card interface");
    if (mingw_load_symbols())
        return NULL;
    scard = os_zalloc(sizeof(*scard));
    if (scard == NULL)
        return NULL;

    ret = SCardEstablishContext(SCARD_SCOPE_SYSTEM, NULL, NULL,
            &scard->ctx);
    if (ret != SCARD_S_SUCCESS) {
        wpa_printf(MSG_DEBUG, "SCARD: Could not establish smart card "
                "context (err=%ld)", ret);
        goto failed;
    }

    ret = SCardListReaders(scard->ctx, NULL, NULL, &len);
    if (ret != SCARD_S_SUCCESS) {
        wpa_printf(MSG_DEBUG, "SCARD: SCardListReaders failed "
                "(err=%ld)", ret);
        goto failed;
    }

#ifdef UNICODE
    len *= 2;
#endif /* UNICODE */
    readers = os_malloc(len);
    if (readers == NULL) {
        wpa_printf(MSG_INFO, "SCARD: malloc failed\n");
        goto failed;
    }

    ret = SCardListReaders(scard->ctx, NULL, readers, &len);
    if (ret != SCARD_S_SUCCESS) {
        wpa_printf(MSG_DEBUG, "SCARD: SCardListReaders failed(2) "
                "(err=%ld)", ret);
        goto failed;
    }
    if (len < 3) {
        wpa_printf(MSG_WARNING, "SCARD: No smart card readers "
                "available.");
        goto failed;
    }
    /* readers is a list of available reader. Last entry is terminated with
     * double NUL.
     * TODO: add support for selecting the reader; now just use the first
     * one.. */
#ifdef UNICODE
    wpa_printf(MSG_DEBUG, "SCARD: Selected reader='%S'", readers);
#else /* UNICODE */
    wpa_printf(MSG_DEBUG, "SCARD: Selected reader='%s'", readers);
#endif /* UNICODE */

    ret = SCardConnect(scard->ctx, readers, SCARD_SHARE_SHARED,
            SCARD_PROTOCOL_T0, &scard->card, &scard->protocol);
    if (ret != SCARD_S_SUCCESS) {
        if (ret == (long) SCARD_E_NO_SMARTCARD)
            wpa_printf(MSG_INFO, "No smart card inserted.");
        else
            wpa_printf(MSG_WARNING, "SCardConnect err=%lx", ret);
        goto failed;
    }

    os_free(readers);
    readers = NULL;

    wpa_printf(MSG_DEBUG, "SCARD: card=0x%x active_protocol=%lu (%s)",
            (unsigned int) scard->card, scard->protocol,
            scard->protocol == SCARD_PROTOCOL_T0 ? "T0" : "T1");

    ret = SCardBeginTransaction(scard->card);
    if (ret != SCARD_S_SUCCESS) {
        wpa_printf(MSG_DEBUG, "SCARD: Could not begin transaction: "
                "0x%x", (unsigned int) ret);
        goto failed;
    }
    transaction = 1;

    blen = sizeof(buf);

    scard->sim_type = SCARD_GSM_SIM;
    if (sim_type == SCARD_USIM_ONLY || sim_type == SCARD_TRY_BOTH) {
        wpa_printf(MSG_DEBUG, "SCARD: verifying USIM support");
        if (_scard_select_file(scard, SCARD_FILE_MF, buf, &blen,
                    SCARD_USIM, NULL, 0)) {
            wpa_printf(MSG_DEBUG, "SCARD: USIM is not supported");
            if (sim_type == SCARD_USIM_ONLY)
                goto failed;
            wpa_printf(MSG_DEBUG, "SCARD: Trying to use GSM SIM");
            scard->sim_type = SCARD_GSM_SIM;
        } else {
            wpa_printf(MSG_DEBUG, "SCARD: USIM is supported");
            scard->sim_type = SCARD_USIM;
        }
    }

    if (scard->sim_type == SCARD_GSM_SIM) {
        blen = sizeof(buf);
        if (scard_select_file(scard, SCARD_FILE_MF, buf, &blen)) {
            wpa_printf(MSG_DEBUG, "SCARD: Failed to read MF");
            goto failed;
        }

        blen = sizeof(buf);
        if (scard_select_file(scard, SCARD_FILE_GSM_DF, buf, &blen)) {
            wpa_printf(MSG_DEBUG, "SCARD: Failed to read GSM DF");
            goto failed;
        }
    } else {
        unsigned char aid[32];
        int aid_len;

        aid_len = scard_get_aid(scard, aid, sizeof(aid));
        if (aid_len < 0) {
            wpa_printf(MSG_DEBUG, "SCARD: Failed to find AID for "
                    "3G USIM app - try to use standard 3G RID");
            os_memcpy(aid, "\xa0\x00\x00\x00\x87", 5);
            aid_len = 5;
        }
        wpa_hexdump(MSG_DEBUG, "SCARD: 3G USIM AID", aid, aid_len);

        /* Select based on AID = 3G RID from EF_DIR. This is usually
         * starting with A0 00 00 00 87. */
        blen = sizeof(buf);
        if (_scard_select_file(scard, 0, buf, &blen, scard->sim_type,
                    aid, aid_len)) {
            wpa_printf(MSG_INFO, "SCARD: Failed to read 3G USIM "
                    "app");
            wpa_hexdump(MSG_INFO, "SCARD: 3G USIM AID",
                    aid, aid_len);
            goto failed;
        }
    }

    /* Verify whether CHV1 (PIN1) is needed to access the card. */
    pin_needed = scard_pin_needed(scard, buf, blen);
    if (pin_needed < 0) {
        wpa_printf(MSG_DEBUG, "SCARD: Failed to determine whether PIN "
                "is needed");
        goto failed;
    }
    if (pin_needed) {
        scard->pin1_required = 1;
        wpa_printf(MSG_DEBUG, "PIN1 needed for SIM access");
    }

    ret = SCardEndTransaction(scard->card, SCARD_LEAVE_CARD);
    if (ret != SCARD_S_SUCCESS) {
        wpa_printf(MSG_DEBUG, "SCARD: Could not end transaction: "
                "0x%x", (unsigned int) ret);
    }

    return scard;

failed:
    if (transaction)
        SCardEndTransaction(scard->card, SCARD_LEAVE_CARD);
    os_free(readers);
    scard_deinit(scard);
    return NULL;
}


/**
 * scard_set_pin - Set PIN (CHV1/PIN1) code for accessing SIM/USIM commands
 * @scard: Pointer to private data from scard_init()
 * @pin: PIN code as an ASCII string (e.g., "1234")
 * Returns: 0 on success, -1 on failure
 */
int scard_set_pin(struct scard_data *scard, const char *pin)
{
    if (scard == NULL)
        return -1;

    /* Verify whether CHV1 (PIN1) is needed to access the card. */
    if (scard->pin1_required) {
        if (pin == NULL) {
            wpa_printf(MSG_DEBUG, "No PIN configured for SIM "
                    "access");
            return -1;
        }
        if (scard_verify_pin(scard, pin)) {
            wpa_printf(MSG_INFO, "PIN verification failed for "
                    "SIM access");
            return -1;
        }
    }

    return 0;
}


/**
 * scard_deinit - Deinitialize SIM/USIM connection
 * @scard: Pointer to private data from scard_init()
 *
 * This function closes the SIM/USIM connect opened with scard_init().
 */
void scard_deinit(struct scard_data *scard)
{
    long ret;

    if (scard == NULL)
        return;

    wpa_printf(MSG_DEBUG, "SCARD: deinitializing smart card interface");
    if (scard->card) {
        ret = SCardDisconnect(scard->card, SCARD_UNPOWER_CARD);
        if (ret != SCARD_S_SUCCESS) {
            wpa_printf(MSG_DEBUG, "SCARD: Failed to disconnect "
                    "smart card (err=%ld)", ret);
        }
    }

    if (scard->ctx) {
        ret = SCardReleaseContext(scard->ctx);
        if (ret != SCARD_S_SUCCESS) {
            wpa_printf(MSG_DEBUG, "Failed to release smart card "
                    "context (err=%ld)", ret);
        }
    }
    os_free(scard);
    mingw_unload_symbols();
}


static long scard_transmit(struct scard_data *scard,
        unsigned char *_send, size_t send_len,
        unsigned char *_recv, size_t *recv_len)
{
    long ret;
    unsigned long rlen;

    wpa_hexdump_key(MSG_DEBUG, "SCARD: scard_transmit: send",
            _send, send_len);
    rlen = *recv_len;
    ret = SCardTransmit(scard->card,
            scard->protocol == SCARD_PROTOCOL_T1 ?
            SCARD_PCI_T1 : SCARD_PCI_T0,
            _send, (unsigned long) send_len,
            NULL, _recv, &rlen);
    *recv_len = rlen;
    if (ret == SCARD_S_SUCCESS) {
        wpa_hexdump(MSG_DEBUG, "SCARD: scard_transmit: recv",
                _recv, rlen);
    } else {
        wpa_printf(MSG_WARNING, "SCARD: SCardTransmit failed "
                "(err=0x%lx)", ret);
    }
    return ret;
}


static int _scard_select_file(struct scard_data *scard, unsigned short file_id,
        unsigned char *buf, size_t *buf_len,
        sim_types sim_type, unsigned char *aid,
        size_t aidlen)
{
    long ret;
    unsigned char resp[3];
    unsigned char cmd[50] = { SIM_CMD_SELECT };
    int cmdlen;
    unsigned char get_resp[5] = { SIM_CMD_GET_RESPONSE };
    size_t len, rlen;

    if (sim_type == SCARD_USIM) {
        cmd[0] = USIM_CLA;
        cmd[3] = 0x04;
        get_resp[0] = USIM_CLA;
    }

    wpa_printf(MSG_DEBUG, "SCARD: select file %04x", file_id);
    if (aid) {
        wpa_hexdump(MSG_DEBUG, "SCARD: select file by AID",
                aid, aidlen);
        if (5 + aidlen > sizeof(cmd))
            return -1;
        cmd[2] = 0x04; /* Select by AID */
        cmd[4] = aidlen; /* len */
        os_memcpy(cmd + 5, aid, aidlen);
        cmdlen = 5 + aidlen;
    } else {
        cmd[5] = file_id >> 8;
        cmd[6] = file_id & 0xff;
        cmdlen = 7;
    }
    len = sizeof(resp);
    ret = scard_transmit(scard, cmd, cmdlen, resp, &len);
    if (ret != SCARD_S_SUCCESS) {
        wpa_printf(MSG_WARNING, "SCARD: SCardTransmit failed "
                "(err=0x%lx)", ret);
        return -1;
    }

    if (len != 2) {
        wpa_printf(MSG_WARNING, "SCARD: unexpected resp len "
                "%d (expected 2)", (int) len);
        return -1;
    }

    if (resp[0] == 0x98 && resp[1] == 0x04) {
        /* Security status not satisfied (PIN_WLAN) */
        wpa_printf(MSG_WARNING, "SCARD: Security status not satisfied "
                "(PIN_WLAN)");
        return -1;
    }

    if (resp[0] == 0x6e) {
        wpa_printf(MSG_DEBUG, "SCARD: used CLA not supported");
        return -1;
    }

    if (resp[0] != 0x6c && resp[0] != 0x9f && resp[0] != 0x61) {
        wpa_printf(MSG_WARNING, "SCARD: unexpected response 0x%02x "
                "(expected 0x61, 0x6c, or 0x9f)", resp[0]);
        return -1;
    }
    /* Normal ending of command; resp[1] bytes available */
    get_resp[4] = resp[1];
    wpa_printf(MSG_DEBUG, "SCARD: trying to get response (%d bytes)",
            resp[1]);

    rlen = *buf_len;
    ret = scard_transmit(scard, get_resp, sizeof(get_resp), buf, &rlen);
    if (ret == SCARD_S_SUCCESS) {
        *buf_len = resp[1] < rlen ? resp[1] : rlen;
        return 0;
    }

    wpa_printf(MSG_WARNING, "SCARD: SCardTransmit err=0x%lx\n", ret);
    return -1;
}


static int scard_select_file(struct scard_data *scard, unsigned short file_id,
        unsigned char *buf, size_t *buf_len)
{
    return _scard_select_file(scard, file_id, buf, buf_len,
            scard->sim_type, NULL, 0);
}


static int scard_get_record_len(struct scard_data *scard, unsigned char recnum,
        unsigned char mode)
{
    unsigned char buf[255];
    unsigned char cmd[5] = { SIM_CMD_READ_RECORD /* , len */ };
    size_t blen;
    long ret;

    if (scard->sim_type == SCARD_USIM)
        cmd[0] = USIM_CLA;
    cmd[2] = recnum;
    cmd[3] = mode;
    cmd[4] = sizeof(buf);

    blen = sizeof(buf);
    ret = scard_transmit(scard, cmd, sizeof(cmd), buf, &blen);
    if (ret != SCARD_S_SUCCESS) {
        wpa_printf(MSG_DEBUG, "SCARD: failed to determine file "
                "length for record %d", recnum);
        return -1;
    }

    wpa_hexdump(MSG_DEBUG, "SCARD: file length determination response",
            buf, blen);

    if (blen < 2 || buf[0] != 0x6c) {
        wpa_printf(MSG_DEBUG, "SCARD: unexpected response to file "
                "length determination");
        return -1;
    }

    return buf[1];
}


static int scard_read_record(struct scard_data *scard,
        unsigned char *data, size_t len,
        unsigned char recnum, unsigned char mode)
{
    unsigned char cmd[5] = { SIM_CMD_READ_RECORD /* , len */ };
    size_t blen = len + 3;
    unsigned char *buf;
    long ret;

    if (scard->sim_type == SCARD_USIM)
        cmd[0] = USIM_CLA;
    cmd[2] = recnum;
    cmd[3] = mode;
    cmd[4] = len;

    buf = os_malloc(blen);
    if (buf == NULL)
        return -1;

    ret = scard_transmit(scard, cmd, sizeof(cmd), buf, &blen);
    if (ret != SCARD_S_SUCCESS) {
        os_free(buf);
        return -2;
    }
    if (blen != len + 2) {
        wpa_printf(MSG_DEBUG, "SCARD: record read returned unexpected "
                "length %ld (expected %ld)",
                (long) blen, (long) len + 2);
        os_free(buf);
        return -3;
    }

    if (buf[len] != 0x90 || buf[len + 1] != 0x00) {
        wpa_printf(MSG_DEBUG, "SCARD: record read returned unexpected "
                "status %02x %02x (expected 90 00)",
                buf[len], buf[len + 1]);
        os_free(buf);
        return -4;
    }

    os_memcpy(data, buf, len);
    os_free(buf);

    return 0;
}


static int scard_read_file(struct scard_data *scard,
        unsigned char *data, size_t len)
{
    unsigned char cmd[5] = { SIM_CMD_READ_BIN /* , len */ };
    size_t blen = len + 3;
    unsigned char *buf;
    long ret;

    cmd[4] = len;

    buf = os_malloc(blen);
    if (buf == NULL)
        return -1;

    if (scard->sim_type == SCARD_USIM)
        cmd[0] = USIM_CLA;
    ret = scard_transmit(scard, cmd, sizeof(cmd), buf, &blen);
    if (ret != SCARD_S_SUCCESS) {
        os_free(buf);
        return -2;
    }
    if (blen != len + 2) {
        wpa_printf(MSG_DEBUG, "SCARD: file read returned unexpected "
                "length %ld (expected %ld)",
                (long) blen, (long) len + 2);
        os_free(buf);
        return -3;
    }

    if (buf[len] != 0x90 || buf[len + 1] != 0x00) {
        wpa_printf(MSG_DEBUG, "SCARD: file read returned unexpected "
                "status %02x %02x (expected 90 00)",
                buf[len], buf[len + 1]);
        os_free(buf);
        return -4;
    }

    os_memcpy(data, buf, len);
    os_free(buf);

    return 0;
}


static int scard_verify_pin(struct scard_data *scard, const char *pin)
{
    long ret;
    unsigned char resp[3];
    unsigned char cmd[5 + 8] = { SIM_CMD_VERIFY_CHV1 };
    size_t len;

    wpa_printf(MSG_DEBUG, "SCARD: verifying PIN");

    if (pin == NULL || os_strlen(pin) > 8)
        return -1;

    if (scard->sim_type == SCARD_USIM)
        cmd[0] = USIM_CLA;
    os_memcpy(cmd + 5, pin, os_strlen(pin));
    os_memset(cmd + 5 + os_strlen(pin), 0xff, 8 - os_strlen(pin));

    len = sizeof(resp);
    ret = scard_transmit(scard, cmd, sizeof(cmd), resp, &len);
    if (ret != SCARD_S_SUCCESS)
        return -2;

    if (len != 2 || resp[0] != 0x90 || resp[1] != 0x00) {
        wpa_printf(MSG_WARNING, "SCARD: PIN verification failed");
        return -1;
    }

    wpa_printf(MSG_DEBUG, "SCARD: PIN verified successfully");
    return 0;
}


/**
 * scard_get_imsi - Read IMSI from SIM/USIM card
 * @scard: Pointer to private data from scard_init()
 * @imsi: Buffer for IMSI
 * @len: Length of imsi buffer; set to IMSI length on success
 * Returns: 0 on success, -1 if IMSI file cannot be selected, -2 if IMSI file
 * selection returns invalid result code, -3 if parsing FSP template file fails
 * (USIM only), -4 if IMSI does not fit in the provided imsi buffer (len is set
 * to needed length), -5 if reading IMSI file fails.
 *
 * This function can be used to read IMSI from the SIM/USIM card. If the IMSI
 * file is PIN protected, scard_set_pin() must have been used to set the
 * correct PIN code before calling scard_get_imsi().
 */
int scard_get_imsi(struct scard_data *scard, char *imsi, size_t *len)
{
    unsigned char buf[100];
    size_t blen, imsilen, i;
    char *pos;

    wpa_printf(MSG_DEBUG, "SCARD: reading IMSI from (GSM) EF-IMSI");
    blen = sizeof(buf);
    if (scard_select_file(scard, SCARD_FILE_GSM_EF_IMSI, buf, &blen))
        return -1;
    if (blen < 4) {
        wpa_printf(MSG_WARNING, "SCARD: too short (GSM) EF-IMSI "
                "header (len=%ld)", (long) blen);
        return -2;
    }

    if (scard->sim_type == SCARD_GSM_SIM) {
        blen = (buf[2] << 8) | buf[3];
    } else {
        int file_size;
        if (scard_parse_fsp_templ(buf, blen, NULL, &file_size))
            return -3;
        blen = file_size;
    }
    if (blen < 2 || blen > sizeof(buf)) {
        wpa_printf(MSG_DEBUG, "SCARD: invalid IMSI file length=%ld",
                (long) blen);
        return -3;
    }

    imsilen = (blen - 2) * 2 + 1;
    wpa_printf(MSG_DEBUG, "SCARD: IMSI file length=%ld imsilen=%ld",
            (long) blen, (long) imsilen);
    if (blen < 2 || imsilen > *len) {
        *len = imsilen;
        return -4;
    }

    if (scard_read_file(scard, buf, blen))
        return -5;

    pos = imsi;
    *pos++ = '0' + (buf[1] >> 4 & 0x0f);
    for (i = 2; i < blen; i++) {
        unsigned char digit;

        digit = buf[i] & 0x0f;
        if (digit < 10)
            *pos++ = '0' + digit;
        else
            imsilen--;

        digit = buf[i] >> 4 & 0x0f;
        if (digit < 10)
            *pos++ = '0' + digit;
        else
            imsilen--;
    }
    *len = imsilen;

    return 0;
}


/**
 * scard_gsm_auth - Run GSM authentication command on SIM card
 * @scard: Pointer to private data from scard_init()
 * @_rand: 16-byte RAND value from HLR/AuC
 * @sres: 4-byte buffer for SRES
 * @kc: 8-byte buffer for Kc
 * Returns: 0 on success, -1 if SIM/USIM connection has not been initialized,
 * -2 if authentication command execution fails, -3 if unknown response code
 * for authentication command is received, -4 if reading of response fails,
 * -5 if if response data is of unexpected length
 *
 * This function performs GSM authentication using SIM/USIM card and the
 * provided RAND value from HLR/AuC. If authentication command can be completed
 * successfully, SRES and Kc values will be written into sres and kc buffers.
 */
int scard_gsm_auth(struct scard_data *scard, const unsigned char *_rand,
        unsigned char *sres, unsigned char *kc)
{
    unsigned char cmd[5 + 1 + 16] = { SIM_CMD_RUN_GSM_ALG };
    int cmdlen;
    unsigned char get_resp[5] = { SIM_CMD_GET_RESPONSE };
    unsigned char resp[3], buf[12 + 3 + 2];
    size_t len;
    long ret;

    if (scard == NULL)
        return -1;

    wpa_hexdump(MSG_DEBUG, "SCARD: GSM auth - RAND", _rand, 16);
    if (scard->sim_type == SCARD_GSM_SIM) {
        cmdlen = 5 + 16;
        os_memcpy(cmd + 5, _rand, 16);
    } else {
        cmdlen = 5 + 1 + 16;
        cmd[0] = USIM_CLA;
        cmd[3] = 0x80;
        cmd[4] = 17;
        cmd[5] = 16;
        os_memcpy(cmd + 6, _rand, 16);
    }
    len = sizeof(resp);
    ret = scard_transmit(scard, cmd, cmdlen, resp, &len);
    if (ret != SCARD_S_SUCCESS)
        return -2;

    if ((scard->sim_type == SCARD_GSM_SIM &&
                (len != 2 || resp[0] != 0x9f || resp[1] != 0x0c)) ||
            (scard->sim_type == SCARD_USIM &&
             (len != 2 || resp[0] != 0x61 || resp[1] != 0x0e))) {
        wpa_printf(MSG_WARNING, "SCARD: unexpected response for GSM "
                "auth request (len=%ld resp=%02x %02x)",
                (long) len, resp[0], resp[1]);
        return -3;
    }
    get_resp[4] = resp[1];

    len = sizeof(buf);
    ret = scard_transmit(scard, get_resp, sizeof(get_resp), buf, &len);
    if (ret != SCARD_S_SUCCESS)
        return -4;

    if (scard->sim_type == SCARD_GSM_SIM) {
        if (len != 4 + 8 + 2) {
            wpa_printf(MSG_WARNING, "SCARD: unexpected data "
                    "length for GSM auth (len=%ld, expected 14)",
                    (long) len);
            return -5;
        }
        os_memcpy(sres, buf, 4);
        os_memcpy(kc, buf + 4, 8);
    } else {
        if (len != 1 + 4 + 1 + 8 + 2) {
            wpa_printf(MSG_WARNING, "SCARD: unexpected data "
                    "length for USIM auth (len=%ld, "
                    "expected 16)", (long) len);
            return -5;
        }
        if (buf[0] != 4 || buf[5] != 8) {
            wpa_printf(MSG_WARNING, "SCARD: unexpected SREC/Kc "
                    "length (%d %d, expected 4 8)",
                    buf[0], buf[5]);
        }
        os_memcpy(sres, buf + 1, 4);
        os_memcpy(kc, buf + 6, 8);
    }

    wpa_hexdump(MSG_DEBUG, "SCARD: GSM auth - SRES", sres, 4);
    wpa_hexdump(MSG_DEBUG, "SCARD: GSM auth - Kc", kc, 8);

    return 0;
}


/**
 * scard_umts_auth - Run UMTS authentication command on USIM card
 * @scard: Pointer to private data from scard_init()
 * @_rand: 16-byte RAND value from HLR/AuC
 * @autn: 16-byte AUTN value from HLR/AuC
 * @res: 16-byte buffer for RES
 * @res_len: Variable that will be set to RES length
 * @ik: 16-byte buffer for IK
 * @ck: 16-byte buffer for CK
 * @auts: 14-byte buffer for AUTS
 * Returns: 0 on success, -1 on failure, or -2 if USIM reports synchronization
 * failure
 *
 * This function performs AKA authentication using USIM card and the provided
 * RAND and AUTN values from HLR/AuC. If authentication command can be
 * completed successfully, RES, IK, and CK values will be written into provided
 * buffers and res_len is set to length of received RES value. If USIM reports
 * synchronization failure, the received AUTS value will be written into auts
 * buffer. In this case, RES, IK, and CK are not valid.
 */
int scard_umts_auth(struct scard_data *scard, const unsigned char *_rand,
        const unsigned char *autn,
        unsigned char *res, size_t *res_len,
        unsigned char *ik, unsigned char *ck, unsigned char *auts)
{
    unsigned char cmd[5 + 1 + AKA_RAND_LEN + 1 + AKA_AUTN_LEN] =
    { USIM_CMD_RUN_UMTS_ALG };
    unsigned char get_resp[5] = { USIM_CMD_GET_RESPONSE };
    unsigned char resp[3], buf[64], *pos, *end;
    size_t len;
    long ret;

    if (scard == NULL)
        return -1;

    if (scard->sim_type == SCARD_GSM_SIM) {
        wpa_printf(MSG_ERROR, "SCARD: Non-USIM card - cannot do UMTS "
                "auth");
        return -1;
    }

    wpa_hexdump(MSG_DEBUG, "SCARD: UMTS auth - RAND", _rand, AKA_RAND_LEN);
    wpa_hexdump(MSG_DEBUG, "SCARD: UMTS auth - AUTN", autn, AKA_AUTN_LEN);
    cmd[5] = AKA_RAND_LEN;
    os_memcpy(cmd + 6, _rand, AKA_RAND_LEN);
    cmd[6 + AKA_RAND_LEN] = AKA_AUTN_LEN;
    os_memcpy(cmd + 6 + AKA_RAND_LEN + 1, autn, AKA_AUTN_LEN);

    len = sizeof(resp);
    ret = scard_transmit(scard, cmd, sizeof(cmd), resp, &len);
    if (ret != SCARD_S_SUCCESS)
        return -1;

    if (len <= sizeof(resp))
        wpa_hexdump(MSG_DEBUG, "SCARD: UMTS alg response", resp, len);

    if (len == 2 && resp[0] == 0x98 && resp[1] == 0x62) {
        wpa_printf(MSG_WARNING, "SCARD: UMTS auth failed - "
                "MAC != XMAC");
        return -1;
    } else if (len != 2 || resp[0] != 0x61) {
        wpa_printf(MSG_WARNING, "SCARD: unexpected response for UMTS "
                "auth request (len=%ld resp=%02x %02x)",
                (long) len, resp[0], resp[1]);
        return -1;
    }
    get_resp[4] = resp[1];

    len = sizeof(buf);
    ret = scard_transmit(scard, get_resp, sizeof(get_resp), buf, &len);
    if (ret != SCARD_S_SUCCESS || len > sizeof(buf))
        return -1;

    wpa_hexdump(MSG_DEBUG, "SCARD: UMTS get response result", buf, len);
    if (len >= 2 + AKA_AUTS_LEN && buf[0] == 0xdc &&
            buf[1] == AKA_AUTS_LEN) {
        wpa_printf(MSG_DEBUG, "SCARD: UMTS Synchronization-Failure");
        os_memcpy(auts, buf + 2, AKA_AUTS_LEN);
        wpa_hexdump(MSG_DEBUG, "SCARD: AUTS", auts, AKA_AUTS_LEN);
        return -2;
    } else if (len >= 6 + IK_LEN + CK_LEN && buf[0] == 0xdb) {
        pos = buf + 1;
        end = buf + len;

        /* RES */
        if (pos[0] > RES_MAX_LEN || pos + pos[0] > end) {
            wpa_printf(MSG_DEBUG, "SCARD: Invalid RES");
            return -1;
        }
        *res_len = *pos++;
        os_memcpy(res, pos, *res_len);
        pos += *res_len;
        wpa_hexdump(MSG_DEBUG, "SCARD: RES", res, *res_len);

        /* CK */
        if (pos[0] != CK_LEN || pos + CK_LEN > end) {
            wpa_printf(MSG_DEBUG, "SCARD: Invalid CK");
            return -1;
        }
        pos++;
        os_memcpy(ck, pos, CK_LEN);
        pos += CK_LEN;
        wpa_hexdump(MSG_DEBUG, "SCARD: CK", ck, CK_LEN);

        /* IK */
        if (pos[0] != IK_LEN || pos + IK_LEN > end) {
            wpa_printf(MSG_DEBUG, "SCARD: Invalid IK");
            return -1;
        }
        pos++;
        os_memcpy(ik, pos, IK_LEN);
        pos += IK_LEN;
        wpa_hexdump(MSG_DEBUG, "SCARD: IK", ik, IK_LEN);

        return 0;
    }

    wpa_printf(MSG_DEBUG, "SCARD: Unrecognized response");
    return -1;
}
